Method and apparatus for dynamically locating resources

ABSTRACT

Methods and apparatuses for dynamically locating resources. In one aspect of the invention, a method to retrieve a resource for a digital processing system includes: receiving a request for a resource; downloading a first version of the resource from a server through a network connection to satisfy the request if the first version of the resource is retrievable through the network connection; and loading a second version of the resource from a storage device of the digital processing system if the first version of the resource is not retrievable through a network connection. In one example, downloading the first version is performed in response to a determination that the first version of the resource is different from a second version of the resource on a storage device of the digital processing system.

This application is a continuation of co-pending U.S. patent applicationSer. No. 14/469,051 filed on Aug. 26, 2014, which is a continuation ofU.S. patent application Ser. No. 12/790,641 filed on May 28, 2010, nowissued as U.S. Pat. No. 8,838,731, which is a continuation of U.S.patent application Ser. No. 10/263,008, filed Oct. 1, 2002, now issuedas U.S. Pat. No. 7,730,155.

FIELD OF THE INVENTION

The invention relates to digital processing systems, and moreparticularly to dynamically locating resources using network connectionswhen available.

BACKGROUND OF THE INVENTION

On a computer system, a resource is typically specified using a filename with a path (or directory) or a Universal Resource Locator (URL).HyperText Markup Language (HTML) documents use URL addresses to specifythe locations of the resources that are required by these documents orlinked to these documents through hyperlinks.

A complete URL address includes the network protocol for accessing theresource, the host address of the computer on which the resourceresides, the directory in which the resource resides, and the file nameof the resource. For example, URL addresshttp://www.uspto.gov/main/patents.htm specifies that HTML documentpatents.htm is retrievable using Hypertext Transfer Protocol (HTTP) fromdirectory/main of host www.uspto.gov. To retrieve patents.htm, a clientcomputer contacts host www.uspto.gov using HTTP protocol to transferfile /main/patents.html from the HTTP server at www.uspto.gov. Afterreceiving a request from the client for an HTML document, the HTTPserver at the remote host (e.g., www.uspto.gov) typically maps thedirectory (e.g., /main) in the URL to a directory in the file system ofthe server computer to locate the corresponding HTML document specifiedin the URL address.

Relative URL addresses are typically used in an HTML document forspecifying the locations of the resources relative to the location ofthe HTML document. For example, HTML document athttp://www.uspto.gov/main/patents.htm may contain a hyperlink torelative URL address./search.htm. From the base address of HTML documentpatents.htm, it can be determined that the complete address of documentsearch.htm is http://www.uspto.gov/main/search.htm.

URL addresses can also be used to specify resources which reside locallyon a computer system. For example, URL addressfile:///C:/main/patents.htm specifies an HTML document on a local harddrive C. A file on a computer is typically specified as a file name witha path. For example, file name C:/main/patents.htm contains pathC:/main/. A file name with a path can also be considered as a relativeURL address with a default base address (e.g., file:///)

URL addresses specify the exact locations of the corresponding resourcesso that a web browser can retrieve the resources from the locations asspecified in the URL addresses. When the storage locations of theresources are moved (e.g., from a remote server to a local file system),the corresponding URL addresses for accessing these resources arechanged accordingly in order to access the resources from the newlocations. When relative URL addresses are used, only the base addressesare changed accordingly. The complete addresses for the relative URLaddresses are changed automatically to reflect the changes in the baseaddresses, since the complete addresses for the relative URL addressesare computed from the base addresses and the relative URL addresses.

A web browser typically maintains a cache that stores some of the filesretrieved from remote servers through a network connection. Such a webbrowser may use the resource stored in the cache to display a documentwhen it assumes or determines that the resource on the remote server hasnot changed since the resource was downloaded and cached. For example,when the forward (or back) button on a web browser is pressed, theprevious downloaded and cached version of the resource is used, assumingthat there has been no change in the resource. When no networkconnection to the server is available, a web browser typically displaysan error message, even when a version of the resource is previouslydownloaded and cached. A user may manually switch the web browser (e.g.,Internet Explorer) from an online mode to an offline mode (e.g., workoffline). When the web browser is in an offline mode, it can display,without a network connection, the web pages that have already been downloaded in the cache. If the user clicks on a link for a document that isnot in the cache when the web browser is in the offline mode, the webbrowser informs the user that the document is not available in theoffline mode; and the user has the option to keep the web browser in theoffline mode or switch the web browser back to the online mode.

SUMMARY OF THE DESCRIPTION

Methods and apparatuses for dynamically locating resources are describedhere.

In one aspect of the invention, a method to retrieve a resource for adigital processing system includes: receiving a request for a resource;downloading a first version of the resource from a server through anetwork connection to satisfy the request if the first version of theresource is retrievable through the network connection; and loading asecond version of the resource from a storage device of the digitalprocessing system if the first version of the resource is notretrievable through a network connection. In one example according tothis aspect, the network connection is automatically established beforedownloading the first version of the resource from the server, if thenetwork connection is not already established. For example, a modem isinstructed to initiate a connection to establish the network connection.

In one example, downloading the first version is performed in responseto a determination that the first version of the resource is differentfrom the second version of the resource on the storage device of thedigital processing system. Thus, when the server has an updated versionof the resource, the updated version of the resource is downloaded tosatisfy the request. If no network connection to the server is availableor downloading from the server is not successful, the second version ofthe resource from the storage device on the digital processing system isloaded to satisfy the request.

In one example, downloading from the server is performed if it isdetermined that a version of the resource on the server is preferred.The first version of the resource downloaded from the server is storedon the storage device of the digital processing system if downloading issuccessful. If it is determined that a version of the resource on theserver is not preferred, the second version of the resource is loadedfrom the storage device on the digital processing system to satisfy therequest. If a previously downloaded version of the resource exists onthe storage device, the previously downloaded version of the resource isused to satisfy the request. Thus, the second version of the resource isdifferent from the resource, if the second version of the resource is apreviously downloaded version of the resource.

In one example, whether or not a version of the resource on a server ispreferred is determined from a configuration file associated with theresource. An address of the server is also determined from theconfiguration file. In other examples, whether or not a version of theresource on a server is preferred is determined according to systemconditions, and/or a file on a remote server. The address of the servermay be hardwired, or determined from a search at a remote server, ordetermined from a file at a remote server.

The present invention includes methods and apparatuses which performthese methods, including data processing systems which perform thesemethods, and computer readable media which when executed on dataprocessing systems cause the systems to perform these methods.

Other features of the present invention will be apparent from theaccompanying drawings and from the detailed description which follow.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is illustrated by way of example and notlimitation in the figures of the accompanying drawings in which likereferences indicate similar elements.

FIG. 1 shows a block diagram example of a data processing system whichmay be used with the present invention.

FIG. 2 shows a schematic diagram of a system for updating files througha network according to one embodiment of the present invention.

FIG. 3 shows a flow chart of a method to locate a resource according toone embodiment of the present invention.

FIG. 4 shows a detailed flow chart of a method to locate a fileaccording to one embodiment of the present invention.

FIG. 5 illustrates an example flow diagram of a method to determinewhether or not an updated version of a resource is retrievable through anetwork connection according to one embodiment of the present invention.

FIG. 6 illustrates a configuration file for specifying parameters fordynamically locating resources according to one embodiment of thepresent invention.

FIG. 7 illustrates a scheme to specify parameters for dynamicallylocating resources according to one embodiment of the present invention.

DETAILED DESCRIPTION

The following description and drawings are illustrative of the inventionand are not to be construed as limiting the invention. Numerous specificdetails are described to provide a thorough understanding of the presentinvention. However, in certain instances, well known or conventionaldetails are not described in order to avoid obscuring the description ofthe present invention.

FIG. 1 shows one example of a typical computer system which may be usedwith the present invention. Note that while FIG. 1 illustrates variouscomponents of a computer system, it is not intended to represent anyparticular architecture or manner of interconnecting the components assuch details are not germane to the present invention. It will also beappreciated that network computers and other data processing systemswhich have fewer components or perhaps more components may also be usedwith the present invention. The computer system of FIG. 1 may, forexample, be an Apple Macintosh computer.

As shown in FIG. 1, the computer system 101, which is a form of a dataprocessing system, includes a bus 102 which is coupled to amicroprocessor 103 and a ROM 107 and volatile RAM 105 and a non-volatilememory 106. The microprocessor 103, which may be, for example, a G3 orG4 microprocessor from Motorola, Inc. or IBM is coupled to cache memory104 as shown in the example of FIG. 1. The bus 102 interconnects thesevarious components together and also interconnects these components 103,107, 105, and 106 to a display controller and display device 108 and toperipheral devices such as input/output (I/O) devices which may be mice,keyboards, modems, network interfaces, printers, scanners, video camerasand other devices which are well known in the art. Typically, theinput/output devices 110 are coupled to the system through input/outputcontrollers 109. The volatile RAM 105 is typically implemented asdynamic RAM (DRAM) which requires power continually in order to refreshor maintain the data in the memory. The non-volatile memory 106 istypically a magnetic hard drive or a magnetic optical drive or anoptical drive or a DVD RAM or other type of memory systems whichmaintain data even after power is removed from the system. Typically,the non-volatile memory will also be a random access memory althoughthis is not required. While FIG. 1 shows that the non-volatile memory isa local device coupled directly to the rest of the components in thedata processing system, it will be appreciated that the presentinvention may utilize a non-volatile memory which is remote from thesystem, such as a network storage device which is coupled to the dataprocessing system through a network interface such as a modem orEthernet interface. The bus 102 may include one or more buses connectedto each other through various bridges, controllers and/or adapters as iswell known in the art. In one embodiment the I/O controller 109 includesa USB (Universal Serial Bus) adapter for controlling USB peripherals,and/or an IEEE-1394 bus adapter for controlling IEEE-1394 peripherals.

It will be apparent from this description that aspects of the presentinvention may be embodied, at least in part, in software. That is, thetechniques may be carried out in a computer system or other dataprocessing system in response to its processor, such as amicroprocessor, executing sequences of instructions contained in amemory, such as ROM 107, volatile RAM 105, non-volatile memory 106,cache 104 or a remote storage device. In various embodiments, hardwiredcircuitry may be used in combination with software instructions toimplement the present invention. Thus, the techniques are not limited toany specific combination of hardware circuitry and software nor to anyparticular source for the instructions executed by the data processingsystem. In addition, throughout this description, various functions andoperations are described as being performed by or caused by softwarecode to simplify description. However, those skilled in the art willrecognize what is meant by such expressions is that the functions resultfrom execution of the code by a processor, such as the microprocessor103.

A machine readable medium can be used to store software and data whichwhen executed by a data processing system causes the system to performvarious methods of the present invention. This executable software anddata may be stored in various places including for example ROM 107,volatile RAM 105, non-volatile memory 106 and/or cache 104 as shown inFIG. 1. Portions of this software and/or data may be stored in any oneof these storage devices.

Thus, a machine readable medium includes any mechanism that provides(i.e., stores and/or transmits) information in a form accessible by amachine (e.g., a computer, network device, personal digital assistant,manufacturing tool, any device with a set of one or more processors,etc.). For example, a machine readable medium includesrecordable/non-recordable media (e.g., read only memory (ROM); randomaccess memory (RAM); magnetic disk storage media; optical storage media;flash memory devices; etc.), as well as electrical, optical, acousticalor other forms of propagated signals (e.g., carrier waves, infraredsignals, digital signals, etc.); etc.

At least one embodiment of the present invention seeks to dynamicallylocate resources so that an updated version of a resource on a remoteserver is used when the updated version of the resource is accessible.When the updated version of the resource is not accessible (or does notexist), a local version of the resource (e.g., a locally installeddefault version, a local version in a storage medium, such as a CD-ROM,a previously downloaded updated version, which may or may not havealready been installed, or others) is used.

For example, in an HTML-based Help system, elements that appear on apage (e.g., images, audio clips, video clips, etc.) and hyperlinks toother pages are typically specified using URL addresses. Since the URLaddresses specify the exact predetermined locations of the resources, aresource is normally either on the local file system or on a remoteserver. If the location is at the remote server, the resource can beeasily updated; and the updated version of the resource is used afterthe resource is updated at the remote server. However, when the clientcomputer cannot access the server (e.g., through the network), theclient computer cannot retrieve the required resource from the remoteserver to provide the corresponding help document. If the location ofthe item is locally at the client computer, the resource can always beaccessed regardless of the status of the network connectivity. However,a special procedure is required to update the resource (e.g.,downloading and installing a software patch).

FIG. 2 shows a schematic diagram of a system for updating files througha network according to one embodiment of the present invention. Clientcomputer 203 contains resource manager 211, which dynamically locates aresource according to configuration file 217. Local installation 215contains a default version of the resources on a local storage device(e.g., a hard drive, or a CD-ROM), which can always be accessed byclient computer 203, regardless of the status of the network connection.When client computer 203 is connected to network 201 (e.g., Internet,intranet, Local Area Network (LAN), etc.) through communication link 231(e.g., a modem attached to a telephone line, a network interface cardattached to a network cable, a cable modem attached to a cabletelevision network, a transceiver for a wireless communication network,etc), an updated version of the resource can be retrieved from servers,such as server 205 or 207. When downloaded, the updated version of theresource is stored as cached updates 213 on client computer 203 so thatthe updated version of the resource can be used later without resortingto the servers. Configuration file 217 specifies the addresses of theremote servers for updated versions of resources. Configuration file 217can also store additional information, such as whether or not a versionof the resource on the remote server is preferred. When a version of theresource on the remote server is preferred, the remote server is alwayschecked for an updated version when network connection 231 is available;otherwise, either the cached update or the local installation is used.Thus, depending on the configuration parameters in configuration file217, resource manager 211 either retrieves updated versions of theresources for the local installation from one or more servers or loadscache updates or the local installation from a local storage device. Itwill be understood that various different types of protocols (e.g.,HTTP, FTP (File Transfer Protocol)), servers, and network connectionmedia (e.g., ethernet network interface cards, modems for telephonelines, cable television networks, or Digital Subscriber Lines (DSL),transceivers for wireless networks) can be used with various embodimentsof the present invention in retrieving updated versions of resourcesthrough network connections. Methods to dynamically locate the resourcesare described bellow.

FIG. 3 shows a flow chart of a method to locate a resource according toone embodiment of the present invention. Operation 301 receives arequest for a resource (e.g., a help document, an image, a video clip, adevice driver, etc). From a configuration file operation 303 determineswhether or not a remote version of the resource is the preferredversion. If a remote version of the resource is the preferred version,operation 305 determines whether or not a remote version of the resourceis retrievable through a network connection. When a remote version ofthe resource is retrievable through a network connection, operation 315satisfies the request with the remote version of the resource. Ifoperation 305 determines that a remote version of the resource is notretrievable through a network connection, or operation 303 determinesthat a remote version of the resource is not the preferred version,operation 309 is performed to determine whether or not a local versionof the resource is available. When a local version of the resource isavailable, operation 311 satisfies the request with the local version ofthe resource; otherwise, if operation 307 determines that a remoteversion of the resource is retrievable through a network connection,operation 315 satisfies the request with the remote version of theresource. If operation 307 determines that a remote version of theresource is not retrievable through a network connection, operation 313displays a message to indicate that the resource is not available.

FIG. 4 shows a detailed flow chart of a method to locate a fileaccording to one embodiment of the present invention. After operation401 receives an input of clicking on a link for a file (e.g., bypositioning a mouse controlled cursor on an item, representing a file,displayed on a display screen which is coupled to the mouse and byselecting the item by pressing and releasing a button while the cursoris on the item), operation 403 determines whether or not a remoteupdated version of the file is preferred. If a remote updated version ofthe file is preferred, operation 411 is performed to determine whetheror not a network connection is available; and operation 413 determineswhether or not an updated version of the file is successfully downloadedif a network connection is available. If downloading an updated versionof the file is successful, operation 415 stores the downloaded updatedversion of the file on a local storage device; and operation 405displays the updated version of the file. When no network connection isavailable, or downloading an updated version of the file is notsuccessful, it is concluded that no remote version is retrievable inoperation 417; and operation 419 is performed to determine whether ornot it is already determined that no local version is available. If itis already determined that no local version is available, operation 409displays an error message to indicate the error condition “resourceunavailable”; otherwise, operation 421 is performed. If operation 403determines that a remote updated version of the file is not preferred,operation 421 is performed to determine whether or not an updatedversion of the file is already cached in a local storage device; andoperation 423 determines whether or not a default local version ispresent if no updated version of the file is cached. If an updatedversion of the file is already stored locally, operation 405 displaysthe updated version of the file. If a default local version is present,operation 407 displays the default version of the file. When no updatedversion of the file is stored locally and no default local version ispresent, it is concluded that no local version is available in operation425; and operation 427 is performed to determine whether or not it isalready determined that no remote version is retrievable. If it isalready determined that no local version is retrievable, operation 409displays an error message; otherwise, operation 411 is performed.

FIG. 5 illustrates an example flow diagram of a method to determinewhether or not an updated version of a resource is retrievable through anetwork connection according to one embodiment of the present invention.Operation 501 determines whether or not a network connection is alive.If no network connection is alive and operation 511 determines thatthere is a method to establish a network connection, operation 513attempts to establish a network connection (e.g., instruct a modem tocall an Internet service provider, etc.). If operation 515 determinesthat the attempt to establish a network connection is successful,operation 503 is performed. If there is no method to establish a networkconnection, or the attempt to establish a network connection failed, itis concluded that an updated version of the resource is not retrievablethrough a network connection in operation 517. If operation 501determines that a network connection is alive and operation 503determines that there is an updated version of the resource on a remoteserver, operation 505 attempts to download the updated version of theresource from the remote server. If operation 507 determines thatdownloading the updated version of the resource is successful, it isconcluded that an updated version of the resource is retrievable througha network connection in operation 509. If operation 503 determines thatthere is no updated version of the resource at a remote server, oroperation 507 determines that downloading the updated version of theresource is not successful, it is concluded that an updated version ofthe resource is not retrievable through a network connection inoperation 517.

FIGS. 4 and 5 show example sequences of checking for an updated versionof resources from a remote server, cached updates, and localinstallation. From this description, it will be apparent to one skilledin the art that various different sequences can be used or configuredusing configuration parameters. For example, it may be configured thatthe cached updates are searched first for an updated version of theresource before attempting to contact the remote server for an updatedversion. Further, some resources are frequently used. Thus, it is notdesirable to check the remote server for an update version every timethese resources are used. Thus, control parameters can be used to limitthe frequency to check the remote server for the updated version. Forexample, an HTML document can have a tag to specify when a cacheddocument expires; or the resource manager can maintain a defaultfrequency for checking the remote server; or such a frequency relatedconfiguration parameter for checking the remote server can be specifiedin the configuration file.

Further various methods can be used to determine whether or not theupdated version of the resource on the server is different from (or morerecent than) a version on the local storage device. For example, “HTTPconditional get” can be used to download a resource that is modified. AnHTTP server that meets the HTTP 1.1 specification returns “304 File NotModified” to indicate that the resource on the server is the same asthat in the cached updates. In another embodiment of the invention, aversion number is used to determine whether the server contains anupdate version for the resource.

FIG. 6 illustrates a configuration file for specifying parameters fordynamically locating resources according to one embodiment of thepresent invention. Configuration file 601 contains entry 603 whichspecifies whether or not the resource controlled by the configurationfile is “internet primary”. If it is “internet primary”, a remoteupdated version is preferred; otherwise, a remote updated version is notpreferred. Typically, when the resource is newly released, it can be setto “internet primary” so that updates can be delivered to the users assoon as the updates are available on the server; when the final versionof the resource is released or the product is no longer supported, theconfiguration parameter can be updated to turn off “internet primary”(e.g., when an update version of the configuration file is downloaded asa resource used for determining configuration parameters), and thus thelocal version is the preferred (and current) version.

Configuration file 601 also contains entry 605 which specifies theremote content base address. In one embodiment of the present invention,the remote content base address is in the URL format. Thus, the addressof the remote server and the protocol to contact the remote server forretrieval are included in the remote content base address. A resourcecontrolled by the configuration file can be accessed from a locationrelative to the remote content base address. In one embodiment of thepresent invention, the updated version of a resource having a URLaddress relative to the configuration file is located at the samerelative address with respect to the remote content base address. Forexample, if: i) the configuration file is MacHelp/configuration, ii) theresource controlled by the configuration file is MacHelp/Mail/index.htm,and iii) the remote content base address ishttp://help.apple.com/machelp, then the complete URL for the updatedversion of the resource ishttp://help.apple.com/machcelp/Mail/index.htm. From this description, itwill be apparent to one skilled in the art that various configurationfile formats and options can be used to map an address for a localresource to a remote address for retrieving an updated version of theresource. Furthermore, these configurations can be dynamically changedover time, such that at one point in time, the address for the resourceis a remote server and another, later point in time, it is a first localfile address and at yet another point in time, it is a second local fileaddress. A configuration file can specify a number of alternative remoteor local content base addresses so that the updated version of theresource may be obtained from a number of different alternativelocations. Different protocols (e.g., HTTP, FTP, etc) and serveraddresses may be specified. In other embodiments of the presentinvention, a configuration file can also explicitly specify the remoteaddresses of the updated version of the resources. The configurationinformation can be embedded in certain resource files (e.g., index HTMLfiles), or be stored in separate configuration files.

FIG. 7 illustrates a scheme to specify parameters for dynamicallylocating resources according to one embodiment of the present invention.The locally installed resources are organized in a typical file tree inthe local file system. For example, folder 701 contains help documentson a system. Folders 711□715 located inside folder 701 contain helpdocuments for programs Finder, Sherlock, and Mail respectively. Folders711, 713 and 715 correspond to folders 721, 731 and 741 respectively.Configuration file 717 controls (specifies the configuration parametersfor) the resource files in folder 701. A configuration file in a folderalso recursively controls the resource files in its child folders ofvarious levels that do not have configuration files in the their ownfolders and that do not have configuration files in the correspondingparent folders except the folder itself. For example, folder 741contains no configuration file. Its closest parent folder that has aconfiguration file contains the configuration file that controls theresources in it. Thus, configuration file 717 controls the resources infolder 741. Since folders 721 and 731 contain configuration files 727and 737 respectively, configuration file 717 will not control any of thefiles in folders 721 and 731 and their child folders. When such a schemeis used, existing help systems can be used without modification; and newconfigurations can be easily added to dynamically locate the resourcesaccording to the configuration files. The configuration files can alsohave corresponding remote updated versions. Thus, updated configurationfiles can be accessed from a server to control whether or not the remoteversion is preferred and to specify new locations for updated resources.

A configuration file is illustrated in the above examples to store theindicator of whether or not a version of the resource on a server ispreferred. Whether or not a version of the resource on a server ispreferred can also be determined according to system conditions, and/ora file on a remote server. For example, it may be determined that withina time period (e.g., one year) from a release date of the resource, theversion of the resource on the server is preferred; after a time period(e.g., two years) from the release date, the version of the resource onthe server is not preferred. Alternatively, a determination of whetheror not a remote version of the resource is preferred can be made fromother indicators, such as the release date and the version number of theoperating system, the current date, options previously selected by auser, and others. Further, the address of the server may be hardwired,or determined from a search at a remote server, or determined from afile at a remote server or other locations.

When methods to dynamically locate resources according to variousembodiments of the present invention are used in a Help system, such asa Help system which displays user help information for operating acomputer through a web browser such as Internet Explorer, the latestversion is always used when the client computer is connected to theserver through a network connection (e.g., Internet). When a Help pageis requested, references to the HTML resources are examined to determineif they can be substituted with newer versions on the server. However,if the client computer is not connected to the network, either copies ofrecently retrieved pages are used, or as a last resort, the locallyinstalled files are displayed.

Thus, authors of the Help system don't need to know, or define, whichpart of the Help system will be remotely retrieved. They are free toconcentrate on creating the information without the overhead of decidingwhich topics will be remotely or locally stored. With certainembodiments of the invention, different sections of the Help system canbe designated as being local-only or remote-version-preferred. Thesedesignations can be changed at any time in the life cycle of the helpdocuments, even after the system is installed on the client computer andeven after the user has used the computer for some time. The variousembodiments discussed herein typically use a help viewer program whichmay be a web browser, such as Internet Explorer or Netscape's InternetNavigator. These help viewer programs will typically read the helpinformation files which include addresses which may be modified by theconfiguration files in the manner described herein.

The client computer transparently gets the latest “help” information,when connected to the network; yet the client computer still has fullhelp information available, from the local file system when off thenetwork. When new features are added, or new information about a productis available, the Help system can be silently updated (by, e.g.,updating later versions from a server) and made available to the userswithout the necessity of publicizing and installing updated files andwithout requiring a software or operating system update or upgrade.

Although methods of various embodiments of the present invention areillustrated with URL addresses and HTTP protocol, it will apparent toone skilled in the art from this description that the present inventioncan be used with various different types of schemes for addressing andvarious different types protocols for retrieving resources. Further, theresources that can be dynamically located are not limited to those fordisplaying a document. It will be understood that various types ofresources (e.g., device drivers, program components, packages forlocalization and translation, etc) can be dynamically located (orupdated) using methods of various embodiments of the present invention.

In the foregoing specification, the invention has been described withreference to specific exemplary embodiments thereof. It will be evidentthat various modifications may be made thereto without departing fromthe broader spirit and scope of the invention as set forth in thefollowing claims. The specification and drawings are, accordingly, to beregarded in an illustrative sense rather than a restrictive sense.

What is claimed is:
 1. A method comprising: identifying, by a processorof a client device, a remote location from a plurality of locations fromwhich to obtain a resource, the identifying based on preference criteriaand dynamically changing conditions, and wherein the preference criteriainclude configuration information including an address of the remotelocation for the resource stored on the client device; transparentlyobtaining a later version of the resource from the identified location,wherein an earlier version of the resource, which was previouslyinstalled, is available for use at the client device even when theclient device is disconnected from a network; updating the configurationinformation based upon the obtained later version; and updating theearlier version of the resource with the later version of the resourcefor use by a user of the client device, wherein the updating of theearlier version includes installing the later version of the resource onthe client device.
 2. The method of claim 1, further comprising:responsive to an unsuccessful obtaining of the resource, identifying analternate location from which to obtain the resource.
 3. The method ofclaim 1, wherein the plurality of locations comprises at least one of alocal disk, an optical drive, a disk or drive available through a localarea network (LAN), or a remote server and wherein the resource includesa version number.
 4. The method of claim 1, wherein the dynamicallychanging conditions include system conditions.
 5. The method of claim 1,wherein the preference criteria indicates whether a first version of theresource on a remote server is preferred over any version of theresource stored locally.
 6. The method of claim 1 wherein the resourceincludes one or more program components and wherein the obtainingincludes downloading the later version of the resource and storing thelater version of the resource as a cached update on the client device.7. A non-transitory computer-readable storage medium comprisingexecutable instructions to cause a processing system to performoperations comprising: identifying a remote location from a plurality oflocations from which to obtain a resource, the identifying based onpreference criteria and dynamically changing conditions, and wherein thepreference criteria include configuration information including anaddress of the remote location for the resource stored on a clientdevice; transparently obtaining a later version of the resource from theidentified remote location, wherein an earlier version of the resource,which was previously installed, is available for use at the clientdevice even when the client device is disconnected from a network;updating the configuration information based upon the obtained laterversion; and updating the earlier version of the resource with the laterversion of the resource for use by a user of the client device whereinthe updating of the earlier version includes installing the laterversion of the resource on the client device.
 8. The non-transitorycomputer-readable storage medium of claim 7 further comprisingexecutable instructions to cause the processing system to performoperations comprising: responsive to an unsuccessful obtaining of theresource, identifying an alternate location from which to obtain theresource.
 9. The non-transitory computer-readable storage medium ofclaim 7, wherein the plurality of locations comprises at least one of alocal disk, an optical drive, a disk or drive available through a localarea network (LAN), or a remote server and wherein the resource includesa version number.
 10. The non-transitory computer-readable storagemedium of claim 7, wherein the dynamically changing conditions includesystem conditions.
 11. The non-transitory computer-readable storagemedium of claim 7, wherein the preference criteria indicates whether afirst version of the resource on a remote server is preferred over anyversion of the resource stored locally.
 12. The non-transitorycomputer-readable storage medium of claim 7, wherein the resourceincludes one or more program components and wherein the obtainingincludes downloading the later version of the resource and storing thelater version of the resource as a cached update on the client device.13. A data processing system comprising: a memory; and a processingsystem configurable by instructions stored in the memory to: identify aremote location from a plurality of locations from which to obtain aresource, wherein the identification is based on preference criteria anddynamically changing conditions, wherein the preference criteria includeconfiguration information including an address of the remote locationfor the resource stored on a client device; transparently obtain a laterversion of the resource from the identified remote location, wherein anearlier version of the resource, which was previously installed, isavailable for use at the client device even when the client device isdisconnected from a network; update the configuration information basedupon the obtained later version; and update the earlier version of theresource with the later version of the resource for use by a user of theclient device, wherein the update of the earlier version includesinstalling the later version of the resource on the client device. 14.The data processing system of claim 13 wherein the processing system isfurther configured to identify an alternate location from which toobtain the resource in response to an unsuccessful obtaining of theresource.
 15. The data processing system of claim 13, wherein theplurality of locations comprises at least one of a local disk, anoptical drive, a disk or drive available through a local area network(LAN), or a remote server and wherein the resource includes a versionnumber.
 16. The data processing system of claim 13, wherein thedynamically changing conditions include system conditions.
 17. The dataprocessing system of claim 13, wherein the preference criteria indicateswhether a first version of the resource on a remote server is preferredover any version of the resource stored locally.
 18. The data processingsystem of claim 13, wherein the resource includes one or more programcomponents and wherein the obtaining includes downloading the laterversion of the resource and storing the later version of the resource asa cached update on the client device.
 19. The data processing system ofclaim 13, wherein the dynamically changing conditions further include aperiod since a release date of the resource, and wherein systemconditions include a version number and a release date of an operatingsystem of the client device.
 20. A non-transitory computer-readablestorage medium comprising executable instructions to cause a processingsystem to perform operations comprising: identifying a remote locationfrom a plurality of locations from which to obtain a resource, theidentifying based on preference criteria and dynamically changingconditions, and wherein the preference criteria include configurationinformation including an address of the remote location for the resourcestored on a client device; obtaining a later version of the resourcefrom the identified remote location, wherein an earlier version of theresource, which was previously installed, is available for use at theclient device even when the client device is disconnected from anetwork; updating the configuration information based upon the obtainedlater version; and updating the earlier version of the resource with thelater version of the resource for use by a user of the client devicewherein the updating of the earlier version includes installing thelater version of the resource on the client device.
 21. Thenon-transitory computer-readable storage medium of claim 20 furthercomprising executable instructions to cause the processing system toperform operations comprising: responsive to an unsuccessful obtainingof the resource, identifying an alternate location from which to obtainthe resource.
 22. The non-transitory computer-readable storage medium ofclaim 20, wherein the plurality of locations comprises at least one of alocal disk, an optical drive, a disk or drive available through a localarea network (LAN), or a remote server and wherein the resource includesa version number.
 23. The non-transitory computer-readable storagemedium of claim 20, wherein the dynamically changing conditions includesystem conditions.
 24. The non-transitory computer-readable storagemedium of claim 20, wherein the preference criteria indicates whether afirst version of the resource on a remote server is preferred over anyversion of the resource stored locally.
 25. The non-transitorycomputer-readable storage medium of claim 20, wherein the resourceincludes one or more program components and wherein the obtainingincludes downloading the later version of the resource and storing thelater version of the resource as a cached update on the client device.26. The non-transitory computer-readable storage medium of claim 20wherein the configuration information identifies a plurality ofalternative addresses from which to obtain the later version.